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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Life Cycle Cost of Smart Wayside Object Controller / Livscykelkostnad av Smart Wayside Object Controller

Zarov, Filipp January 2021 (has links)
In a regional railway signalling system, object controllers are the devices responsible for controlling Track Side Equipment and act as interfaces for TSE with the interlocking computer and the Traffic control system. However, associated cabling (signal and power cabling) and civil works pose a major capital investment and it is a source of significant Capital and Operational expenses, particularly in rural areas, where accessibility andconnectivity to power grid and to the interlocking are a problem. Furthermore, cables/signalling equipment are exposed to sabotage and theft in such areas. This can increase the total Life Cycle Cost even further. The Shift2Rail research programme, which was initiated by the European Union and railway stakeholders, tries to address this issue, and revamp the Object Controller concept through the project “TD2.10 Smart radio connectedwayside object controller”, where the aim is to develop a Smart Wayside Object Controller (SWOC). A SWOC is capable of wireless communication between central interlocking and TSE as well as decentralization of interlocking logic. These innovations can reduce the cabling required, increase the availability of diagnostic data, thus reducing maintenance and operational costs and can lead to power saving by utilizing local power sources. The most important impact of the SWOC is a significant reduction of CAPEX, OPEX and of total LCC for an installation utilizing SWOCs, instead of typical OCS.  This work focuses on estimating the LCC of a SWOC system and to compare it with a conventional OCS by developing an LCC model that covers both cases, as well as to use this model to examine when it is more profitable to implement a SWOC, instead of an OCS system. This is done by utilizing LCC analysis and combining a variety of methods in a parametric study. To that extend, a thorough analysis of a modern regional railway signalling system, as well as the basis for LCCA are being discussed. At the same time, both OC and SWOC systems are being described and factors affecting their cost discussed.  The methodology is comprised of the LCC modelling part as well as the collection of methods and techniques used to calculate the LCC of OC/SWOC systems and to estimate the costs of different sub-models and parameters of the process. For the modelling process, the station of Björbo was chosen, which operates under ERTMS-R system, but for the sake of the analysis it is assumed that the typical base system in place is an OCS and together with the existing track layout and equipment it is used as the basis of the analysis. Finally, the formed LCC model is being used in a parametric study to examine how the LCC is affected by using OC or SWOC as well as how LCC responds to changes in parameters such as number of OC/SWOC, traffic density and local power installation cost for the Björbo station. / I ett regionalt järnvägssignalsystem är utdelar de enheter som ansvarar för att kontrollera spårutrustning och fungerar de som gränsyta för spårutrustning med ställverksdatorn och tågtrafikledning systemet. Dock, tillhörande kablar (signalkablar ock kraftkablar), samt anläggningsinfrastruktur utgör en stor kapitalinvestering och de är en källa till märkbar kapitalkostnad och driftskostnader, särskilt på landsbygdsområden, där tillgänglighet och anslutning till elnätet och ställverket är problematisk. Dessutom, kablar och signalutrustning utsätts för stöld och sabotage i sådana områden. Detta kan öka den totala livscykelkostnaden ytterligare. Shift2rail forskningsprogram, som genomförs av EU och järnvägsintressenter, försöker att ta itu med problemet och modernisera utdelar konceptet genom projektet “TD2.10 Smart Radio Connected Wayside Object Controller”, där målet är att utveckla en Smart Spårutrustning Utdelar, så kallade SWOC. En SWOC har kapacitet för trådlös kommunikation mellan central ställverket och spårutrustning, samt decentralisering av satällverkslogiken. Dessa innovationer kan minska nödvändig kabeldragning, öka tillgängligheten av diagnostiska data, vilket minskar underhålls- och driftskostnader och kan leda till energibesparing genom att använda lokala kraftkällor. Den viktigaste effekten av SWOC är en betydande minskning av kapitalkostnader, driftskostnader och totala livscykelkostnaden för en installation som använder SWOC istället för typiska utdelningsystemet. Detta examensarbete fokuserar på att uppskatta LCC för ett SWOC-system och jämföra det med en konventionell utdelingsystem genom att utveckla en LCC-modell som täcker båda fallen, samt att använda denna modell för att undersöka när det är mer lönsamt att implementera en SWOC istället av ett typiskt utdelingsystem. Detta görs genom att använda LCC-analys och kombinera en mängd olika metoder i en parametrisk studie. För att göradetta genomförs en grundlig analys av ett modernt regionalt järnvägssignalsystem, samt grunden för livscykelanalys. Samtidigt beskrivs både ett typiskt utdelingssystem - och SWOC-system samt faktorer som påverkar deras kostnad deskuteras. Metoden består av LCC-modelleringsdelen samt insamling av metoder och tekniker som används för att beräkna LCC för OC / SWOC-system och för att uppskatta kostnaderna för olika delmodeller och parametrar för processen. För modelleringsprocessen valdes stationen i Björbo, som arbetar under ERTMS-R-systemet, men för analysens skull antas att det typiska bassystemet på plats är en typisk OCS och tillsammans med befintlig planritning ochkabelplan är används som grund för analys. Slutligen används den bildade LCC-modellen i en parametrisk studie för att undersöka hur LCC påverkas genom att använda OC eller SWOC samt hur LCC reagerar på förändringar i parametrar såsom antal OC / SWOC, trafiktäthet och lokala kraftinstallationskostnader för Björbo-stationen.
92

Análogos experimentais de metacontingências com ordenação do responder dos participantes

Nogueira, Artur Luís Duarte Diniz 01 November 2013 (has links)
Made available in DSpace on 2016-04-29T13:17:50Z (GMT). No. of bitstreams: 1 Artur Luis Duarte Diniz Nogueira.pdf: 1679075 bytes, checksum: 7aa30f806b3dd856005a944f7f9e63b0 (MD5) Previous issue date: 2013-11-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aimed to evaluate the effects of an ordering of participants responding procedure upon the selection and maintenance of interlocking behavioral contingencies and the aggregate outcome by the cultural consequencies. Thus, two experiments were performed with 19 and 14 participants, mostly university students from PUC-SP, from several courses. The experimental task, which was presented and performed using a computer software (Meta 3), was performed in group, three participants each time, featuring a generation. By the end of each generation the oldest participant was substituted by a new naive one. The experimental task consisted in inserting numbers in empty espaces on the computer s screen. The relation between the numbers inserted by the participants and the numbers presented by the computer generated points, the individual consequence; and the relation between the sum of the numbers inserted by a participant and the sum of the numbers inserted by the others genrated bonuses, the cultural consequence. By the end of the participation, each participant was given R$0,01 for each 10 points or bonuses produced, by way of cost assistance. The Experiment 1 began with the forced ordering of participant responding in force, and later, the ordering was withdrawn. The results points out that ocurred operant selection and selecton and selection of the interlocking behavioral contingêncies and aggregate outcome with the ordering of participants responding and maintenance of it, and that when the ordering of responding was suspended, it were not observed any effects on the maintenance of the interlocking behavioral contingencies and aggregate outcome. Experiment 2 started without the ordering of participants responding, which was put in force after production of bonuses stability for five genarations was reached. The interlocking behavioral contingencies and the aggregate outcome weres selected and mantained throughout the experiment, without suffering any ruptures after the insertion of the ordering of participants responding. Thus, it was concluded that the ordering of participants responding didn t produce any observable effects upon the selection and maintenance of the interlocking behavioral contingencies and aggregate outcome / O objetivo deste trabalho foi avaliar os efeitos de um procedimento de ordenação do responder dos participantes sobre a seleção e a manutenção de contingências comportamentais entrelaçadas e do produto agregado pelas consequências culturais. Para isso, foram realizados dois experimentos com, 19 e 14 participantes, em sua maioria universitários da PUC-SP, de diversos cursos. A tarefa experimental, a qual foi apresentada e realizada utilizando-se um software de computador (Meta 3), foi realizada em grupo, três participantes de cada vez caracterizando uma geração. Ao final de cada geração o participante mais antigo era substituído por um novo participante, ingênuo em relação à atividade experimental, a qual consistiu em inserir números em espaços vazios na tela do computador. A relação entre os números inseridos pelos participantes e números apresentados pelo computador gerava pontos, a consequência individual; e a relação entre as somas dos números inseridos pelo participante e as somas dos números inseridos pelos outros participantes gerava bônus, a consequência cultural. Ao final da participação, cada participante recebeu R$0,01 por cada 10 pontos ou bônus produzidos, a título de ajuda de custos. O Experimento 1 começou com a ordenação forçada do responder dos participantes em vigor, e, posteriormente, foi retirada a ordenação. Os resultados indicam que houve seleção operante e das contingências comportamentais entrelaçadas e produto agregado com a ordenação do responder dos participantes e manutenção dos mesmos, e que quando a ordenação do responder foi removida, não se observou qualquer efeito na manutenção das contingências comportamentais entrelaçadas e do produto agregado. O Experimento 2 teve início sem a ordenação forçada do responder dos participantes, a qual foi colocada em vigor após a estabilidade da produção de bônus por cinco gerações. As contingências comportamentais entrelaçadas e o produto agregado foram selecionados e se mantiveram durante todo o experimento, não sofrendo qualquer ruptura após a inserção da ordenação do responder dos participantes. Concluiu-se, assim, que a ordenação do responder não produziu efeito observável sobre a seleção e a manutenção de contingências comportamentais entrelaçadas e produto agregado
93

New approaches to composite metal joining

Joesbury, Adam Michael January 2015 (has links)
This thesis explores new methods for achieving load-carrying joints between the dissimilar materials of continuous fibre reinforced polymer matrix composites and structural metals. The new composite-to-metal joining methods investigated in this work exploit the metal-to-metal joining techniques of arc micro-welding, resistance spot welding, and metal filler brazing, to form novel micro-architectured metal adherends that can be used for enhanced composite-to-metal joining. Through a combination of equipment instrumentation and metallographic inspection of fabricated prototype joints, understanding is gained of how materials respond when processed by manufacturing techniques that have not previously been exploited for dissimilar material joining. Mechanical testing of prototype joints; both to ultimate loading strength and partial failure states, with subsequent inspection of specimens and comparative performances evaluation enabled joining performance characterisation of the new joining methods. Key results include: the identification of micropin reinforced adhesive joints to exhibit pseudo-ductile failure characteristics, resistance spot weld reinforcement of adhesive joints to boost bonding performance, and the use of a polymer infused metal foam to overcome difficulties of thermoplastic to metal adhesion. Through this work knowledge of how novel micro-architectures reacted under mechanical loading enabled insights to be gained into how perceived manufacturing defects can benefit joining performance. Such examples include, localised material weakness that lead to global pseudo-ductile failure behaviour, and low-strength secondary joining mechanisms boosting primary load transfer systems. By comparison of the diverse joining methods investigated in this work, trends were identified that suggest joining performance between the two dissimilar materials is improved by increasing the direct interaction between the composite reinforcement fibres and the metal structure. It is demonstrated that joining improvements are gained by forming mechanical connections between metals and composite precursory material before the final manufacturing process of the composite.
94

Les effets des liens personnels interconseils sur la performance de l'entreprise : une analyse comparée entre France et Allemagne / Der Einfluss von Aufsichtsratsverflechtungen auf die Unternehmensperformance : ein deutsch-französischer Vergleich

Prinz, Enrico 02 July 2010 (has links)
Bien que le thème des liens interconseils fasse régulièrement l’objet de discussions supposant un effet disciplinaire négatif du cumul de mandats, l’inventaire de la littérature empirique ne permet pas d’obtenir une image claire concernant l’impact des réseaux d’administrateurs sur la performance des entreprises liées. La divergence des résultats s’explique tant par la mobilisation de grilles théoriques négligeant des éléments importants des liens personnels, que des divers critères utilisés pour mesurer la création de valeur. Dans l’objectif d’obtenir des réponses plus concluantes concernant l’impact du partage d’administrateurs communs sur la création de valeur de la firme, nous avons modélisé, à l’aide d’une structure théorique « bi-céphale », les contributions potentielles des liens interconseils à la performance. Notre modèle repose sur la théorie synthétique de la gouvernance. Il mobilise deux voies d’intervention disciplinaire (la surcharge temporelle des « cumulards » et l’effet de réputation exercé par le marché du travail des administrateurs externe) et trois leviers cognitifs (l’apport d’informations et de connaissances, l’apport de compétences généralistes et spécifiques, ainsi que leur combinaison et l’exploitation). À ces facteurs s’ajoutent différentes variables médiatrices et de contrôle. Pour tester la validité de notre modèle, nous avons mené une étude empirico-comparative des liens interconseils existant entre les plus grandes entreprises françaises et allemandes, observés sur la période 2001-2005. Dans la partie descriptive, nous avons examiné, tant pour un échantillon bi-national que pour des sous-échantillons, les caractéristiques des réseaux d’administrateurs contemporains de part et d’autre du Rhin. La partie empirique teste, à l’aide de régressions en données de panel, l’influence des liens sur deux mesures de performance (un critère ex ante et un indicateur ex post). Les tests montrent que les effets de liens interconseils varient selon le type de mandats cumulés. De surcroît, le modèle confirme les contributions supposées importantes des administrateurs multimandats en termes cognitifs et leur impact majoritairement favorable sur la création de valeur. L’anticipation des effets des liens interconseils par les marchés s’avère plus forte que ce que montre l’analyse de leur influence sur la mesure de performance ex post. / Although interlocking directorates are regularly associated with a negative connotation, empirical evidence is far away from offering convincing answers about the performance effects of directorship interlocks. The huge variety of contradicting results can be explained both by the use of different theoretical frameworks and different value creation measures. In order to shed more light on the question of the role of busy directors, we develop a two-pillar model explaining the potential contributions of directorship interlocks to shareholder value creation. Based on a synthetic view of corporate governance, the model uses two disciplinary (work overload of busy directors and incentive effects coming from the external labor market of corporate directors) as well as three cognitive intervention levers (provision of information and knowledge, provision of general and specific competences, combination and exploitation of those elements). Moderating and controlling variables are added. The appropriateness of the model is tested through a 5-year comparison (2001-2005) of director networks within the largest French and German companies. We first present, both for a bi-national sample and national sub-samples, the major characteristics of the identified interlocks. In the empirical part, we conduct a panel data analysis checking for the influence of busy directors on corporate performance. We use two performance measures: one ex ante, the other ex post. Empirical tests indicate that the performance effect of interlocks depend on the type of board seats accumulated. Moreover, statistical modeling confirms the existence of cognitive contributions of director networks and shows mostly positive effects on value creation. Also, markets seem to anticipate director effects – both negative and positive – in a stronger way than an ex post performance analysis shows. / Obgleich das Thema „personelle Unternehmensverflechtungen über den Aufsichtsrat“ re-gelmäßig im Fokus öffentlicher Diskussionen steht – wobei in der Regel eine negative Wirkung der Mandatekumulation auf die Kontrolleffizienz des Überwachungsgremiums und damit letztlich auf die Unternehmensperformance unterstellt wird –, zeigt eine Analyse der empirischen Litera-tur, dass insbesondere in Kontinentaleuropa eine klare Schlussfolgerung hinsichtlich der Wirkung von Mehrfachmandaten auf die Wertschöpfung für die Aktionäre nicht möglich ist. Ursache für die starke Divergenz der Ergebnisse scheint sowohl die Verwendung verschiedener theoretischer Erklärungsmodelle als auch die Mobilisierung unterschiedlicher Messgrößen der Unternehmens-performance zu sein. Mit dem Ziel aussagekräftigere Ergebnisse zur Rolle der Mehrfachmandate und ihres Einflusses auf die Wertschöpfung zu erhalten, untersucht die nachfolgende Studie unter Zuhilfenahme eines 2-Säulen-Modells die verschiedenen potenziellen Wirkungen von Aufsichts-ratsverbindungen auf den Shareholder Value. Das erklärende Modell basiert auf einer erweiterten Governance-Theorie. Hierbei werden neben zwei traditionellen, die Disziplin im Kontrollorgan beeinflussenden Aspekte (zeitliche Überlastung der Mehrfachmandatsträger, Reputationseffekt des externen Arbeitsmarktes für Aufsichtsräte), drei kognitiv-strategische Einflüsse (Zugang zu Informationen und Kenntnissen, Einbringung genereller und spezifischer Kompetenzen, Zusam-menführung und Nutzbarmachung dieser Faktoren) modelliert. Außerdem werden diverse Media-tor- und Kontrollvariablen hinzugefügt. Die Gültigkeit des entwickelten Modelles wurde in einer vergleichen empirischen Analyse der Aufsichtsratsverflechtungen der größten deutschen und französischen Aktiengesellschaften für den Zeitraum 2001-2005 überprüft. Im deskriptiven Teil werden sowohl für eine 2-Länder-Stichprobe als auch für die nationalen Stichproben die Haupt-merkmale der Aufsichtsratsnetzwerke auf beiden Seiten des Rheins dargestellt. Im empirischen Teil wird mittels Panel-Regressionen der Einfluss der Verflechtungen auf zwei Performancemaβe untersucht (ein ex ante- und ein ex post-Indikator). Die Analysen zeigen, dass die Wirkung der Verflechtungen von der Art der zugrunde liegenden Mandatekumulation abhängen. Auf kogniti-ver Ebene können die unterstellten positiven Einflüsse von Mehrfachmandaten auf die Perfor-mance mehrheitlich bestätigt werden. Zudem kann festgestellt werden, dass die Kapitalmärkte deutlich stärker auf personelle Verflechtungsaspekte reagieren als es eine ex post-Analyse der Wertschöpfung vermuten lässt.
95

Revize systému Jidoka / Jidoka system review

Turková, Daniela January 2011 (has links)
The goal of this thesis was to devise appropriate improvements for the quality control tool JIDOKA used in Continental Automotive Systems Czech Republic s.r.o based in Frenštát pod Radhoštěm. First, three areas of concern requiring improvement pro-posals were identified. These were: visualization of the maximum amount of rejects, physical handling of rejects and documentation updates. This work comprises an introduction to the issue and the company, application principles of JIDOKA in Continental company and a description of the areas of concern. As a conclusion, solution proposals for given areas and their implementation are presented.
96

Hotel v Brně / Hotel in Brno

Michna, Martin January 2017 (has links)
In this thesis are solved the newly built 'hotel in Brno ". The building is freestanding. It has five storeys. The structural system is reinforced concrete skeleton. Columns in combination with masonry infill Porotherm. The building is based on the footings. The building has two height levels. The first is covered with a flat roof vegetation and the second single-roof bitumen sheets. The building is insulated contact system. On the first floor is a reception, restaurant with kitchen, fitness center and facilities for the hotel staff. The second floor of the portion used for guest accommodation. The second part is a cafe with cold kitchen and meeting room attached to the bar. In the third to fifth floors are guest rooms and technical background. On the fifth floor are apartments
97

Ein Beitrag zur Systematisierung und Weiterentwicklung der Stellwerks-Energieversorgung

Kunze, Michael 28 October 2015 (has links)
Wegen ihrer großen Bedeutung für die Verfügbarkeit der Stellwerke thematisiert die vorliegende Arbeit den Teilbereich der Energieversorgungsanlagen von Stellwerken. Ausgehend von aktuellen Fragestellungen werden neun Forschungsfragen definiert. Zunächst werden die Grundlagen sowie der Forschungsstand im Bereich der Energieversorgung untersucht. Anschließend erfolgt eine Analyse der historischen Entwicklung der Energieversorgung in der Stellwerkstechnik auf Grundlage einer umfangreichen Literaturrecherche. Darauf folgend werden aktuelle und zukünftige Entwicklungen auf diesem Gebiet untersucht. Im Hauptteil der Arbeit erfolgt eine Fokussierung auf die Energieversorgung von Relaisstellwerken. Die derzeit eingesetzten Anlagen werden hinsichtlich Technik, Altersstruktur und Zustand nebst Störungen analysiert. Dazu werden umfangreiche statistische Auswertungen vorgenommen. Im Anschluss wird ein universelles Erneuerungskonzept zur Ausrüstung der vorhandenen Stellwerke mit modernen Energieversorgungen vorgestellt. Durch die Untersuchung von Entscheidungskriterien wird ermittelt, wann unterschiedliche Erneuerungsvarianten eingesetzt werden sollten. In einer Lebenszykluskostenrechnung (LCC) mit anschließender Wirtschaftlichkeitsrechnung (WKR) werden diese Umbauvarianten monetär bewertet und miteinander verglichen. / Due to its importance for the availability of interlockings, this PhD thesis focuses on the part of the interlockings power supply systems. Based on current issues, nine research questions are defined. First, the basics as well as the present state of the art in research and technology in the field of power supply are examined. This is followed by an analysis of the historical development of interlocking power supply systems based on a substantial literature research. Subsequently, the current and future key developments in this field are investigated. The main part of the work focuses on power supply systems of relay interlockings. The systems currently used are analysed regarding technology, aging and present condition as well as incidents. For that purpose comprehensive statistical evaluations are conducted. After that, a universal concept for replacement of old power supplies by state-of-the-art technology in existing interlocking systems is presented. By studying decision-making-criteria, the appropriate application of different renewal variants is determined. In a life-cycle-costing (LCC) and follow-up cost effective analysis (WKR) the different variants are evaluated and compared with each other.
98

Analys av lågspänningsfördelning till signalanläggningar / Analysis of low voltage power distribution to signalling installations

Pedral, Jacques, Abriren, Josef January 2016 (has links)
I denna rapport utreds hur systemdesignen av lågspänningsfördelningen för järnvägen kan kostnadseffektiviseras. I dagsläget har det utarbetats en norm kring systemdesignen som tenderar att efterbildas från år till år vilket har medfört brist på innovation inom området. Syftet med arbetet var att designa två typstationer med signalställverken M11 respektive M95, där placering samt nominell storlek av UPS:er skulle fastställas för att tillhandahålla en kostnadseffektiv lösning. Dessutom skulle kablage dimensioneras för typstationerna samt se över möjligheten att ersätta UPS:er med likriktarsystem. Stationerna baserades på två redan existerande driftplatser, Fagersta C (M11) och Skänninge (M95). Slutligen skulle olika energilagringsalternativ för UPS-system jämföras för att tillhandahålla det lämpligaste alternativet. Genom simuleringar och beräkningar i bland annat datorprogrammet El-Vis har lågspänningsfördelningen dimensionerats för typstationerna. Arbetet visar på att ett distribuerat UPS-system är att föredra ur ett ekonomiskt perspektiv gentemot ett centraliserat UPS-system. Vidare har det konstaterats att likriktarsystemet Rectiverter kan ersätta UPS:er samt att ackumulatorer är det mest passande energilagringsalternativet. / This report identifies how the system design of low voltage power distribution of the railway can be more cost effective. In the current situation there is a norm on the system design that tends to be replicated each year. This has brought a lack of innovation in the field. The purpose of the thesis was to come up with two model stations with the interlocking system M11 respectively M95, where the positioning and nominal size of the UPS:s would be determined to provide a cost effective solution. Furthermore, the cable dimensioning of the model stations was computed as well as the possibility of replacing UPS-systems with rectifier-systems. The model stations were based on two already existing operating sites, Fagersta C (M11) and Skänninge (M95). Lastly, different energy storage alternatives for UPS-systems were compared to acquire the most appropriate choice. Through simulations and calculations in, inter alia, the computer program El-Vis, the low voltage power distribution was dimensioned for the model stations. The thesis shows that a distributed UPS-system is preferred in an economical point of view compared to a centralized UPS-system. Furthermore, the thesis establishes that the rectifier system Rectiverter can replace UPS:s. It also states that accumulators are the most suitable alternative for energy storage.
99

INTEGRATION OF CONTROL SYSTEMS INTO INTERLOCKING MATERIALS

Ethan West Guenther (13163403) 28 July 2022 (has links)
<p>  </p> <p>Architectured materials offer engineers more options for choosing materials with their desired properties. Segmenting materials to create topological interlocking materials (TIMs) creates materials, which can deform in greater amounts without failure and absorb more strain energy. Previous research on TIMs has shown that the stiffness and reaction force of these materials can be directly controlled by controlling the boundary forces offered by the frame which constrains these materials.</p> <p>The research presented in this paper investigated a TIM made into a 1-Dimension beam like structure called a lintel. This research investigated not only the mechanics of this structure, but also developed a method of directly controlling the reaction force at a given displacement using shape memory alloy (SMA) wires. These wires would actuate the boundary pieces used to constrain the system. These actuation wires coupled with force sensors imbedded into the lintel allowed a feedback control loop to be established, which would control the reaction force. The reaction force was then controlled to create a smart structure which could optimize the strain energy absorption under the constraint of a maximum allowable load, similar to cellular solids used in packaging and padding materials.</p> <p>To develop this smart structure, four separate investigations occurred. The first was finite element analysis (FEA) performed to model the loading response of the lintel. This experiment demonstrated that the Mises Truss Model was effective at modelling the lintel. The second was an experimental validation of the FEA model performed in the first investigation. This experiment validated the Mises Truss Model for the lintel. The third investigation simulated the active lintel using computational software and the model of the lintel established in the first two investigations. This experiment demonstrated computationally the ability of SMA wires to control the reaction force as desired in an idealized case. The fourth and final investigation experimentally validated the ability to create and active lintel and created a functioning prototype. This demonstrated experimentally the ability of the active lintel to control reaction force as desired.</p> <p>This project has demonstrated the viability to create smart structures using segmented materials, which in the future may be used in a variety of applications including robotics and adaptive structures in harsh environments. </p>
100

Exploring Intersectionality, Unravelling Interlocking Oppression: Feminist Non-credit Learning Practices

McKenzie, Christine 12 September 2011 (has links)
The concepts of intersectionality and interlocking identities came out of needs raised by communities and then academics wrote about it. This dissertation examines these concepts and how these resonate with the ways that feminist educators conceptualize and facilitate non-credit learning processes with women. This research focuses on 10 differently-located feminist educators and the processes they lead that meet a range of learning goals. Specifically, this research examines the learning practices that these educators used to help women learners gain a consciousness around their identity and issues of power and oppression. I then discuss how these practices resonate with the theoretical frameworks of intersecting and interlocking oppressions. Anti-oppression, feminist informed research and feminist standpoint theories informed the research approach. The Critical Appreciative Process, which builds on the Appreciative Inquiry (AI) method, was used to explore what is working within feminist non-credit learning processes. In addition, two case studies were elaborated on in order to examine the learning practices that were particularly successful. The educators reflected on several barriers involved in bringing differently-located women together to explore and address the power dynamics associated with power and oppression. These included the defensiveness, denial and avoidance associated with acknowledging and addressing privilege. The educators also shared effective practices for addressing such barriers. Key practices included creating an environment for difficult conversations, working intergenerationally, using theoretical frameworks to deconstructing interpersonal dynamics occurring in the group and providing tools to draw on everyday experiences and challenge (inappropriate) behaviours. Additionally, specific activities for raising learners’ awareness of their own complex and multiple identities and how these identities are co-constructed through interactions with others were detailed. This study revealed the limitations of intersectionality and interlocking identities frameworks in praxis, as well as the ways in which an awareness of identity, difference and power creates an entry point for intersectional and interlocking awareness that aids feminist movements. This research makes a contribution to strengthening the praxis of feminist educators facilitating non-credit processes. Within feminist theorizing, this research also makes an important contribution in contextualizing intersectionality and interlocking identities frameworks within a range of feminist non-credit learning practices.

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